I did play Arp 2600 as well an an Arp String Ensemble and an Arp Pro Soloist on that track. But what you’re hearing–the random sequence that runs through the entire track and that plays alone for the first 10 seconds or so–isn’t played by anyone. And, no, it’s not a Quica! Jim Cooper, a West Coast audio engineer and designer, approached me a few weeks before we went into the studio to record the album and showed me a device he’d come up with that he called The Random Resonator. It was basically a clever realization of a sample and hold circuit and the related analog circuits you’d expect–VCA, VC envelope generator,random voltage generator for pitch, white noise generator, VCF, VC clock, etc.–in a little cream-colored box about 4 inches square and 3 inches high. The face panel allowed you to adjust clock speed, degree of filter resonance, filter cut-off, range of randomness, and, as I remember, control over filter and amplifier envelopes. There may have been control knob that allowed you to apply the random voltage to the degree of resonance, but I’m not sure any longer–it’s been more than 40 years!

The Random Resonator wasn’t expensive, but at the time members of Herbie’s band made $300/wk, so I asked Herbie to buy it, which he did. We took it into the studio, set it up to Herbie and David Rubinson’s satisfaction (David was our producer), and Fred Catero, our great engineer, then recorded about 5 or 10 minutes of it onto 1/4″ tape. From that we selected a particularly juicy sequence that was probably a minute long, and we looped that and recorded it onto about 15 minutes of an otherwise blank 2″ 24 track. The band then played live over that. A couple of days later we took the 24 track over to my studio, Different Fur, where Herbie overdubbed handclaps and, I believe, some additional Rhodes. The same day, whether before or after Herbie’s od’s I don’t remember, I recorded probably 4 more tracks of Arp 2600–the first od begins as a pleasant quirky gong-like sound at 11 seconds in. I followed this with what I suppose would be called synth solo od/s–although the whole synth mass, in my mind, should be heard as developments of the Random Resonator. As someone on the thread mentioned, it all seems to be a single synth track. It’s not, but that’s the effect I wanted. The delicious reverb, by the way, was not part of the device, but what Fred added when he mixed.

Update: Jim Cooper himself was kind enough to respond to my requests for more information:

“Pat’s memory is a lot better than mine, I must say. Coincidentally, I recently thought of the Random Resonator, and had a thought that I knew
where I had one squirreled away, but it turned out to be a different limited production gadget. His description of the controls is pretty good, as
I remember.

I think I did make more than two of them, but am not really sure. It’s been a lot of years, and there have been lots of boxes of various sorts since.
I’m pretty sure that one was used on the soundtrack of The Getaway (Quincy Jones), and maybe on Klute, too, but am not sure.”